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Morphological Characterization of Arbuscular Mycorrhizal Fungi Associated with the Rhizosphere According to the Age of Xanthosoma sagittifolium L. Schott Plants in the Field

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American Journal of Plant Sciences 2024年第3期15卷 161-179页

作者： Audrey Maguy Bengono Nyimiebolo Astride Carole Djeuani Hermann Désiré Mbouobda Antoine Marie Kevin Tiki Theresa Akinimbom Moma Diobe Motassy Manuela Samuel Brice Adounga Christophe Fendju Pangueko Jones Nshanji issofa nguetrapouna Rose Theophine Derricka Djem Moutamal A. Ziem Amang Amang Nicolas Niemenak Laboratory of Plant Physiology Department of Biological Sciences Higher Teacher Training College (HTTC) University of Yaoundé I Yaoundé Cameroon Department of Plant Biology Faculty of Sciences University of Yaoundé I Yaoundé Cameroon Department of Biology Higher Teacher Training College Bambili (HTTC) The University of Bamenda Bamenda Cameroon Departments of Microbiology Faculty of Science University of Yaoundé 1 Yaoundé Cameroon

The objective of this work was to carry out a morphological characterization of arbuscular mycorrhizal fungi in the rhizosphere of Xanthosoma sagittifolium L. Schott plants. The plant material used was the white and red cultivars of X. sagittifolium, belonging to age intervals of 3 - 6, 6 - 9, and 9 - 12 months. Three harvest sites were chosen in the Central Region of Cameroon. In each site, soil from the rhizosphere and plant roots was collected in a randomized manner. In the field, the agronomic parameters were evaluated. The physicochemical characteristics of the soils, the mycorrhization index, and the morphological characterization of the mycorrhizal types of each site were carried out. The results obtained show that the agronomic growth parameters varied significantly using the Student Newman and Keuls Test depending on the harvest sites. The soils’ pH in all sites was acidic and ranged between 4.6 and 5.8. The Nkometou site has a loamy texture while the Olembe and Soa sites have loam-clay-sandy and loam-clay textures respectively. The highest mycorrhization frequencies appeared at the Nkometou site, with 75 and 87.33% of the white and red cultivars plant roots at 6 - 9 and 3 - 6 months. The relative abundance of AMF arbuscular mycorrhizal fungal spores in the rhizosphere of X. sagittifolium plants varied with age and cultivar. There were 673 spores between 9 - 12 months in Nkometou in the red cultivar. Six AMF genera were identified in all the different soils collected: Acaulospora sp., Funneliformis sp., Gigaspora sp., Glomus sp., Scutellospora sp., and Septoglomus sp. The genus Glomus sp. was the most present at all age intervals in both cultivars.

关键词： Xanthosoma sagittifolium L. Schott Rhizosphere Harvest Site Arbuscular Mycorrhizal Fungi Diversity

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Strawberry (Fragaria spp.): Cultivation, Production, Consumption, and Marketing in Cameroon

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Agricultural Sciences 2024年第4期15卷 449-471页

作者： Djeuani Astride Carole Moutamal Djem Rose Theophine Derricka Mbouobda Hermann Désiré Abdoulaye Souaibou Meliga Essimi Célestine Bouopda Nono Joël Anafack Donasson Dioril Messouang Bernard Didier Ndongo III Boris Charlen Kaffo Emmanuel Kamga Fossouo Anselme Xavier Tiki Antoine Marie Kevin Nyimiebolo Bengono Audrey Maguy Manuela Diobe Motassy Adounga Samuel Brice Amama Amama Benjamin Nshanji Jones Panguepko Fendju Christophe Nzie Oussena nguetrapouna issofa Mpon Ikoyin Linda NKouéya Christelle Ladone Amang Amang A. Ziem Niemenak Nicolas Laboratory of Plant Physiology and Biochemistry Department of Biological Sciences Higher Teachers&#8217 Training College University of Yaound&#233 1 Yaound&#233 Cameroon Department of Plant Biology Faculty of Science University of Yaound&#233 1 Yaound&#233 Cameroon Department of Biology Higher Teachers&#8217 Training College Bambili University of Bamenda Bamenda Cameroon Mbidjoro Sustainable Living Environment Ngaound&#233r&#233 Cameroon Cé r&#232s Agricole Yaound&#233 Cameroon KAFFO Farm Baham Cameroon Agro Ankh Dschang Cameroon Bio Farm of Lolodorf Lolodorf Cameroon Or Rouge d’ Afrique Obala Cameroon Bafoussam Farm Bafoussam Cameroon King Farms Baham Cameroon Department of Microbiology Faculty of Science University of Yaound&#233 1 Yaound&#233 Cameroon

Strawberry (Fragaria spp.) is one of the most important fruits classified as exotic fruits imported into Cameroon. To have an inventory of its cultivation in Cameroon, a survey study was carried out among eight farms of Fragaria spp. from January 2021 to February 2022. The plant was introduced in Cameroon in 2018. There are 13 varieties of Fragaria spp. currently cultivated. Among these 13 varieties, eleven are hybrids of Fragaria x ananassa (“Amiga”, “Amine”, “Camarosa”, “Chandler”, “Charlotte”, “Elsanta”, “Gariguette”, “Madame Moutot”, “Ostara”, “Ruby gem” and “San Andreas”), and two of the hybrids of Fragaria vesca (“Maestro” and “Mara des bois”). The cropping system, irrigation system, and type of fertilizers applied differ from one strawberry farm to another. Biofertilizers (such as mycorrhizal), inorganic and organic fertilizers are actually used to improve production. The potential annual production of strawberries from January 2021 to February 2022, estimated based on the survey data, was 21.216 tons for all growers. Among these eight production farms, the Lolodorf BIO Farm presents 6000 kg (six tons) of strawberries and 100,000 stolons (seedlings) produced, from seven varieties of Fragaria spp. cultivated, with 6 varieties which are hybrids variety Fragaria x ananassa (“Amiga”, “Amine”, “Chandler”, “Gariguette”, “Madame Moutot”, and “Ruby gem”), and one which is a hybrid of Fragaria vesca (“Mara des bois”). Certain diseases were also observed and recorded depending on the growing areas.

关键词： Fragaria spp. Cultivation Technique Attack of Pathogens Annual Production Cameroon

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Effects of Shannon entropy and electric field on polaron in RbCl triangular quantum dot

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Chinese Physics B 2016年第4期25卷 432-435页

作者： M Tiotsop A J Fotue S C Kenfack N issofa H Fotsin L C Fai Mesoscopic and Multilayers Structures Laboratory Department of Physics Faculty of Science University of Dschang Laboratory of Electronics and Signal Processing Department of Physics Faculty of Science University of Dschang

In this paper, the time evolution of the quantum mechanical state of a polaron is examined using the Pekar type variational method on the condition of the electric-LO-phonon strong-coupling and polar angle in RbC1 triangular quantum dot. We obtain the eigenenergies, and the eigenfunctions of the ground state, and the first excited state respectively. This system in a quantum dot can be treated as a two-level quantum system qubit and the numerical calculations are performed. The effects of Shannon entropy and electric field on the polaron in the RbC1 triangular quantum dot are also studied.

关键词： Shannon entropy polaron electric field triangular quantum dot

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Work Done on a Coherently Driven Quantum System

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Journal of Quantum Information Science 2015年第3期5卷 89-102页

作者： issofa Nsangou Lukong Cornelius Fai Mesoscopic and Multilayer Structures Laboratory Faculty of Science Department of Physics University of Dschang Yaounde Cameroon

We calculate the work done by a Landau-Zener-like dynamical field on two- and three-level quantum system by constructing a quantum power operator. We elaborate a general theory applicable to a wide range of closed-quantum system. We consider the dynamics of the system in the time domain ]-tLZ,tLZ[ (where is the LZ transition time in the sudden limit) where the external pulse changes its sign and its action becomes relevant. The statistical work is evaluated in a period [0,T] where T ≤tLZ. Our results are observed to be in good qualitative agreement with known results.

关键词： Power Operator Statistical Work Landau-Zener Model Level Crossing

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Energy levels of magneto-optical polaron in spherical quantum dot—Part 1:Strong coupling

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Journal of Semiconductors 2015年第9期36卷 1-8页

作者： A.J.Fotue S.C.Kenfack N.issofa M.Tiotsop H.Fotsin E.Mainimo L.C.Fai Mesoscopic and Multilayers Structures Laboratory Department of PhysicsFaculty of ScienceUniversity of Dschang Laboratory of Electronics and Signal Processing Department of PhysicsFaculty of ScienceUniversity of Dschang

We investigate the influence of a magnetic field on the ground state energy of a polaron in a spherical semiconductor quantum dot （QD） using the modified LLP method. The ground state energy is split into sub-energy levels and there is a degeneracy of energy levels. It is also observed that the degenerate energy increase with the electron-phonon coupling constant and decrease with the magnetic field. The numerical results show that, under the influence of magnetic field and the interaction with the total momentum along the z-direction, the split energy increases and decreases with the longitudinal and the transverse confinement length, respectively.

关键词： magnetic field total momentum modified LLP polaron energy quantum dot

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Electric and magnetic optical polaron in quantum dot—Part 1: strong coupling

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Journal of Semiconductors 2015年第7期36卷 1-6页

作者： A.J.Fotue N.issofa M.Tiotsop S.C.Kenfack M.P.Tabue Djemmo H.Fotsin and L.C.Fai Mesoscopic and Multilayers Structures Laboratory Department of PhysicsFaculty of ScienceUniversity of Dschang Laboratory of Mechanics and Modeling of Physical Systems Faculty of ScienceUniversity of Dschang Laboratory of Electronics and Signal Processing Department of PhysicsFaculty of ScienceUniversity of Dschang

We investigated the influence of electric field and magnetic field on the ground state energy ofpolaron in spherical semiconductor quantum dot （QD） using a modified Lee Low Pines （LLP） method. The numerical results show the increase of the ground state energy with the increase of the electric field and the decreasing with the magnetic field. The modulation of the electric field, magnetic field and the confinement lengths lead to the control of the decoherence of the system.

关键词： electric field magnetic field modified LLP polaron energy quantum dot

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PEP-PAN@PSf rods for extraction of EDCs in fish and chicken tissues followed by UPLC-MS/MS assay

PEP-PAN@PSf rods for extraction of EDCs in fish and chicken ...

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中国化学会第十三届全国分析化学年会

作者： Sabour issofa Bonfoh 李丹熊朝梅 Department of pharmaceutical analysis School of Pharmacy Tongji Medical College Huazhong University of Science and Technology

Synthesized endocrine disrupting chemicals(EDCs) are randomly discharged into environment, popularly discovered in food samples, and in return interfere with organism hormone systems at certain doses. Commercial polar enhanced polymer(PEP, 40-60 μm, 70 ?, 600 m/g) shows good adsorption towards both polar and nonpolar compounds due to the presence of hydrophobic and hydrophilic functional groups on surface. In the study, PSf HFM supported PEP-PAN rods(PEP-PAN@PSf rods) were prepared by dipping PEP-PAN slurry on polysulfone hollow fiber membrane(PSf HFM) coated stainless steel rods, without conventional pre-corrosion of bare stainless steel rods by strong acid. The rods showed good biocompatibility and long-term stability during application. Under the optimal conditions, the PEP-PAN@PSf rods coupled with UPLC-MS/MS was subjected for analysis of seven EDCs(E3, BPA, E2, EE2, E1, DES, DE) in fish and chicken tissues

关键词： PEP-PAN@PSf rods endocrine disrupting chemicals(EDCs) fish chicken

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Electro-magnetic weak coupling optical polaron and temperature effect in quantum dot

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Journal of Semiconductors 2015年第10期36卷 9-15页

作者： M.Tiotsop A.J.Fotue S.C.Kenfack N.issofa A.V.Wirngo M.P.Tabue Djemmo H.Fotsin L.C.Fai Mesoscopic and Multilayers Structures Laboratory Department of PhysicsFaculty of ScienceUniversity of Dschang Laboratory of Mechanics and Modeling of Physical Systems Faculty of ScienceUniversity of Dschang Laboratory of Electronics and Signal Processing Department of PhysicsFaculty of ScienceUniversity of Dschang

We investigate the influence of the electric field and magnetic fields on the ground state energy of a polaron in a spherical semiconductor quantum dot （QD） using the modified Lee Low Pines （LLP） method. The numerical results show the increase of the ground state energy with the increase of the electric field and the electron- phonon coupling constant, and the decrease with the magnetic field and the longitudinal confinement length. It is also seen that the temperature is an increasing function of the cyclotron frequency and the coupling constant whereas it decreases with the electric field strength. The modulation of the electric field, the magnetic field and the confinement length leads to the control of decoherence in the system.

关键词： electric field magnetic field modified LLP polaron energy quantum dot temperature

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Comparative Theoretical Studies of the Reactivity and Stability of Selected Groups of Isomers with Carbon-Oxygen and Carbon-Nitrogen Bonds

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Computational Chemistry 2021年第2期9卷 120-130页

作者： issofa Patouossa Eric N. Njabon Alphonse Emadak Naomi Zshika Unit of Physical and Theoretical Chemistry of the Laboratory of Applied Physical and Analytical Chemistry Faculty of Sci-ences University of Yaoundé I Yaoundé I Cameroon

Electronic structure calculations have been carried out to study various closely related isomers with propane backbone which form part of our quantum chemical approach to inter and intra-molecular kinetics. The usefulness of UCA-FUKUI developed by Jesús Sánchez-Márquez to facilitate the theoretical study of chemical reactivity is exploited. All isomers are identified as local minima with single-point calculations on DFT/B3LYP/6-31G(d,p). The increasing order of stability by groups of isomers are group I;propn-2-ol, propan-1-ol, group II;propanone, propanal, group III;Ethylmethanoate, Propanoic acid, Methylethanoate, group IV;N,N-dimethylformamide, propanimino, and propanamide. The trend in reactivity of the various groups of isomers and specific points of nucleophilic and electrophilic attacks are presented. We noticed that most of the properties of these isomers taught at the fundamental levels are proven true theoretically.

关键词： Electronic Structure Isomers Chemical Reactivity Stability Nucleophilic and Electrophilic Attacks

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Thermodynamic Parameters of Central Spin Coupled to an Antiferromagnetic Bath: Path Integral Formalism

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Journal of Applied Mathematics and Physics 2021年第1期9卷 133-145页

作者： Christian Platini Fogang Kuetche Nsangou issofa Mathurin Esouague Ateuafack Lukong Cornelius Fai Research Unity of Condensed Matter Electronics and Signal Processing Department of Physics Faculty of Science University of Dschang Dschang Cameroon Department of Research Development Innovation and Training SpaceKola Yaounde Cameroon Department of Electrical and Electronic Engineering College of Technology University of Buea Buea Cameroon

A path-integral representation of central spin system immersed in an antiferromagnetic environment was investigated. To carry out this study, we made use of the discrete-time propagator method associated with a basic set involving coherent states of Grassmann variables which made it possible to obtain the analytical propagator which is the centerpiece of the study. In this study, we considered that the environment was in the low-temperature and low-excitation limit and was split into 2 subnets that do not interact with each other. The evaluation of our system was made by considering the first neighbor approximation. From the formalism of the path integrals, it is easy to evaluate the partition function and thermodynamic properties followed from an appropriate tracing over Grassmann variables in the imaginary time domain. We show that the energy of the system depends on the number of sites n when β → 0.

关键词： Path Integral Grassmann Algebra Antiferromagnetic Environment Partition Function

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